CVE - CVE-2021-43799

CVE-ID
CVE-2021-43799	Learn more at National Vulnerability Database (NVD) • CVSS Severity Rating • Fix Information • Vulnerable Software Versions • SCAP Mappings • CPE Information
Description
Zulip is an open-source team collaboration tool. Zulip Server installs RabbitMQ for internal message passing. In versions of Zulip Server prior to 4.9, the initial installation (until first reboot, or restart of RabbitMQ) does not successfully limit the default ports which RabbitMQ opens; this includes port 25672, the RabbitMQ distribution port, which is used as a management port. RabbitMQ's default "cookie" which protects this port is generated using a weak PRNG, which limits the entropy of the password to at most 36 bits; in practicality, the seed for the randomizer is biased, resulting in approximately 20 bits of entropy. If other firewalls (at the OS or network level) do not protect port 25672, a remote attacker can brute-force the 20 bits of entropy in the "cookie" and leverage it for arbitrary execution of code as the rabbitmq user. They can also read all data which is sent through RabbitMQ, which includes all message traffic sent by users. Version 4.9 contains a patch for this vulnerability. As a workaround, ensure that firewalls prevent access to ports 5672 and 25672 from outside the Zulip server.
References
Note: References are provided for the convenience of the reader to help distinguish between vulnerabilities. The list is not intended to be complete.
CONFIRM:https://github.com/zulip/zulip/security/advisories/GHSA-p663-wxvv-2fjp URL:https://github.com/zulip/zulip/security/advisories/GHSA-p663-wxvv-2fjp MISC:https://github.com/gteissier/erl-matter URL:https://github.com/gteissier/erl-matter MISC:https://github.com/zulip/zulip/commit/a5496f4098e3998c9b84e8dc564aa983d6cdf6e8 URL:https://github.com/zulip/zulip/commit/a5496f4098e3998c9b84e8dc564aa983d6cdf6e8 MISC:https://github.com/zulip/zulip/releases/tag/4.9 URL:https://github.com/zulip/zulip/releases/tag/4.9
Assigning CNA
GitHub (maintainer security advisories)
Date Record Created
20211116	Disclaimer: The record creation date may reflect when the CVE ID was allocated or reserved, and does not necessarily indicate when this vulnerability was discovered, shared with the affected vendor, publicly disclosed, or updated in CVE.
Phase (Legacy)
Assigned (20211116)
Votes (Legacy)

Comments (Legacy)

Proposed (Legacy)
N/A
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